This study is a randomized open-label multi-center (multi-national) two year study evaluating body mass composition and bone density in patients with childhood onset growth hormone deficient (GHD) after being treated with growth hormone for two years after attaining adult height. The hypothesis is that growth hormone is needed in adults for maintaining normal body composition. The intent of this study is to evaluate whether patients treated with growth hormone for two years after epiphyseal closure show any significant difference in body mass composition as compared to young adults with GHD in whom GH treatment is discontinued. Further, this study will evaluate differences in body composition in children continuing on the standard pediatric doses as compared to those children treated with standard adult doses. Children treated with GH until attainment of final height will be treated with both adult doses (0.3 mg rhGH per day) and pediatric doses (0.4mg/kg/day) for 2 years and body mass composition and bone density assessed by DEXA before and after treatment. At this time 2 patients are enrolled in the study. A third patient recruited for the study and begun on rhGH developed a recurrence of an astrocytoma. This was not drug related because an earlier MRI of the brain demonstrated probable recurrence.